This is an application for renewal of a program project grant involving many investigators and many different projects all relating to the improvement of the results of organ transplantation. This grant has been operative for seven years and it is organizationally complex. It has been traditionally divided into two major sections: Clinical Investigations of human organ transplantation and Experimental Investigations utilizing animals. This organization persists in this application for renewal. The basic overall objectives have been to: (a) analyze and isolate the clinical problems involved in organ transplantation and precisely document clinical-laboratory correlations; (b) organize clinical trials based on available data to solve clinical problems; (c) generate experimental solutions to these problems which can ultimately be applied to the clinical problem. Within these objectives, there are four essential AIMS in clinical transplantation under which our projects are organized: AIM 1 - To Prevent organ destruction by the host; AIM 2 - To counteract infection: AIM 3 - To maximize rehabilitation; AIM 4 - To maintain patient and organ in optimal condition prior to and during transplantation. Within these broad aims, the clinical investigation focus on the continued development of antilymphoblast globulin (ALG), the problems of the diabetic patient, histological indices of prognosis, immunological monitoring, viral infections and their prevention, quantitative indices of rehabilitation, hemodialysis and organ preservation. The experimental section pursues parallel aims stressing basic biological problems of immunology, kidney transplantation in dogs and rats, establishing models for ALG assessment, experimental viral infections and organ preservation.